1. Field of the Invention
The present invention relates to the field of particle collection. More particularly, the present invention relates to collection of particles from the air onto filters and the rapid, efficient elution of these particles from flat filters into a liquid sample.
2. Background of the Invention
The difficulties of detecting and quantifying particles in air and liquids are well known. Existing systems all begin to fail as concentration decreases until, eventually with diminished concentrations of analyte, there is an inability to detect at all. This poses a significant problem to national security where, for example, the postal anthrax attacks of 2001 and the subsequent war on terrorism have revealed shortcomings in the sampling and detection of biothreats. The medical arts are similarly affected by the existing limits on detection, as are the environmental sciences.
In the fields of biodefense and aerosol research it is common to collect aerosols into a liquid sample using a wet cyclone or similar device. The aerosol is collected into an aqueous sample so that subsequent analysis of biological particles can be performed using standard techniques that primarily require that the sample be contained in liquid. These “wet” collectors have many failings including difficulty in maintaining a set fluid volume and difficulties with buildup of particle matter in the device.
Dry filters have long been used for collection of aerosols, as well as for collection of particles from liquids. However, dry filters fail for the use of identifying biological particles primarily because it is difficult to remove the particles into a liquid. Methods for removing particles from flat or fiber-based depth filters are common but are tedious and often very inefficient. What is needed is a system, method, or device to efficiently remove particles from a flat filter without corrupting the captured sample.